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Author Topic: Huge Difference Between Labs  (Read 263 times)

AWesker

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Huge Difference Between Labs
« on: March 28, 2019, 06:59:33 pm »
tl:dr; Same Estradiol test at LabCorp and Quest are wildly different.

I've been on TRT for a while now and am still having a hard time getting everything dialed in. I have other problems besides Testosterone though, so even if my Test and E2 are perfect I still won't feel great (low cortisol, thyroid, etc). I have a standing order to get my labs checked every so often, and usually get them done at LabCorp. A few weeks ago I thought I was having high E symptoms (Hard to maintain an erection, soft erections, nipples feel weird, etc) - but, for me, high E and low E feel pretty similar, so I wanted to get my levels checked before I changed anything again. Long story short, if I use my standing order it takes about 2 weeks for the results to show up in the online portal at LabCorp, so I paid out of pocket to get my Estradiol checked at Quest, so I could get the results in a few days. I also went to LabCorp right afterwards to get the full standing order for the rest of the results (Testosterone and DHT).

I just got my results back and it makes no sense - At approximately 7:30 AM I got my blood drawn at Quest. My results:
Estradiol, Ultrasensitive, LC/MS - 32 H - Range: <=29

Then, I immediately drove to LabCorp and got another draw at 8:12 AM. My results:
Estradiol, Sensitive (LC/MS/MS) - 20.9 - Range: 8-35

Since I got the results from Quest first I upped my AI a tiny bit, and maybe felt a little better (like I said, other issues keep my feeling pretty shitty no matter what my T and E2 are). But at LabCorp my Estradiol is almost perfect, maybe a tiny bit low. Like I said, high E and low E feel pretty similar to me, so I'm kind of at a loss as to what to do, or which lab to trust. I don't want to be too high, but I don't want to be too low long term either. Which test is more 'right'? How can you reconcile these two tests? Anyone had this happen before?

Cataceous

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Re: Huge Difference Between Labs
« Reply #1 on: March 28, 2019, 07:48:10 pm »
Two out of six times I've had the LabCorp sensitive test give a result that was about half what it was supposed to be. I can't speak directly to the Quest results, but these mass spectrometry-based tests are still pretty tricky and can be very wrong when not done perfectly. A solution for some is to calibrate with the standard immunoassay test. It is idiot-proof and has been very consistent for me. The problem with these "standard" tests is some cross-reactivity to other molecules, such as C-reactive protein. But if you have low levels of the problem substances then these tests provide a good check against the sensitive tests. I mainly rely on the standard tests now, with only occasional verification via a sensitive test.
I am not a medical doctor; any suggestions are meant to be discussed with your doctor.
Age: 57, Ht: 5'10", Wt: 158 lbs
Protocol: 18 mg T enanthate subQ qod, 250 IU hCG subQ qod, 70 mcg anastrozole qod, 6.25 mg DHEA orally bid
7-12/2018 test results: TT: 800 ng/dL, E2: 31 pg/mL LC/MS-MS, DHEA-S: 264 ug/dL (49-344)—SHBG ~30 nmol/L

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Re: Huge Difference Between Labs
« Reply #1 on: March 28, 2019, 07:48:10 pm »


AlbertRet

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Re: Huge Difference Between Labs
« Reply #2 on: March 30, 2019, 05:12:43 am »
This is mind-blowing. I've not even thought of getting tested at multiple labs, but after seeing this, I think I might.

Cataceous

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Re: Huge Difference Between Labs
« Reply #3 on: March 30, 2019, 06:52:54 am »
Ideally we should avoid basing important treatment decisions on any single test result.
I am not a medical doctor; any suggestions are meant to be discussed with your doctor.
Age: 57, Ht: 5'10", Wt: 158 lbs
Protocol: 18 mg T enanthate subQ qod, 250 IU hCG subQ qod, 70 mcg anastrozole qod, 6.25 mg DHEA orally bid
7-12/2018 test results: TT: 800 ng/dL, E2: 31 pg/mL LC/MS-MS, DHEA-S: 264 ug/dL (49-344)—SHBG ~30 nmol/L

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Re: Huge Difference Between Labs
« Reply #3 on: March 30, 2019, 06:52:54 am »


HRD LVN

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Re: Huge Difference Between Labs
« Reply #4 on: March 30, 2019, 10:40:58 am »
Ideally we should avoid basing important treatment decisions on any single test result.
Sometimes I wish this forum offered a like button.
My LAbCorp has made several mistakes on 6 month checkup blood tests over the years.
My TRT clinic made protocol changes based on them and it cost me 8 months to recover.

Always ask for a retest when you get an outlier.

AWesker

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Re: Huge Difference Between Labs
« Reply #5 on: April 03, 2019, 05:49:30 pm »
Two out of six times I've had the LabCorp sensitive test give a result that was about half what it was supposed to be. I can't speak directly to the Quest results, but these mass spectrometry-based tests are still pretty tricky and can be very wrong when not done perfectly. A solution for some is to calibrate with the standard immunoassay test. It is idiot-proof and has been very consistent for me. The problem with these "standard" tests is some cross-reactivity to other molecules, such as C-reactive protein. But if you have low levels of the problem substances then these tests provide a good check against the sensitive tests. I mainly rely on the standard tests now, with only occasional verification via a sensitive test.

Do you know how the LC/MS/MS test is performed and where the error is coming from? From what I understand, if the immunoassay is 'wrong' it is going to be wrong on the high side due to reacting with other hormones in your blood. With the LC/MS test, if it's 'wrong', is it always going to be wrong on the low side?

This is mind-blowing. I've not even thought of getting tested at multiple labs, but after seeing this, I think I might.

Yep. I've been chasing the E2 number for almost a year now. I've thought I was just crazy super sensitive to arimidex, as in .005 mg (not .05) would change my E2 from being somewhat high to super low. Now maybe the labs are just wrong? I dunno. But I'll be getting the standard E2 test done next time in addition to the LC/MS test to see if that could help.

Cataceous

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Re: Huge Difference Between Labs
« Reply #6 on: April 03, 2019, 07:58:17 pm »
...
Do you know how the LC/MS/MS test is performed and where the error is coming from? From what I understand, if the immunoassay is 'wrong' it is going to be wrong on the high side due to reacting with other hormones in your blood. With the LC/MS test, if it's 'wrong', is it always going to be wrong on the low side?
...

The "standard" immunoassay tests are the ones that tend to err on the high side due to cross-reactivity with other molecules, such as C-reactive protein.

As for mass spectrometry-based tests—LC/MS, etc.—, I don't know the details, but this quote gives a sense of why they can be problematic:

Quote
It needs to be noted that mass spectrometry assays are highly complex and require both a high degree of manual adjustments and controlling of operational conditions. Therefore, a high level of skill and knowledge is required to properly set up and operate these methods. Inappropriately operated mass spectrometry methods can lead to profoundly incorrect and inconsistent results. To facilitate the implementation of mass spectrometry in the clinical laboratory, the Clinical and Laboratory Standards Institute (www.CLSI.org) is developing a series of guidance documents, with one specifically addressing methods for steroid hormones. Furthermore, organizations such as the American Association of Clinical Chemistry (www.AACC.org) are offering training opportunities on mass spectrometry for the clinical laboratory.
I am not a medical doctor; any suggestions are meant to be discussed with your doctor.
Age: 57, Ht: 5'10", Wt: 158 lbs
Protocol: 18 mg T enanthate subQ qod, 250 IU hCG subQ qod, 70 mcg anastrozole qod, 6.25 mg DHEA orally bid
7-12/2018 test results: TT: 800 ng/dL, E2: 31 pg/mL LC/MS-MS, DHEA-S: 264 ug/dL (49-344)—SHBG ~30 nmol/L

AWesker

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Re: Huge Difference Between Labs
« Reply #7 on: May 15, 2019, 11:12:47 am »
So I got another round of E2 labs done, this time including the standard immunoassay method and the LC/MS to compare. Results as follow:

5/4/19, 8:17 AM, Quest Labs:
Estradiol, immunoassay (<= 39) Result: 21
Estradiol, ultrasensitive, LC/MS ( <=29) Result: 30 HIGH

5/4/19, 9:28 AM, LabCorp:
Estradiol, Roche ECLIA immunoassay (7.6 - 42.6) Result: 23.4
Estradiol, Sensitive, LC/MS/MS (8.0 - 35.0) Result: 15.6


So, both tested about an hour apart. The immunoassay results were pretty close, within 10% of each other. The LC/MS - the "gold standard" of estradiol tests, was DOUBLE at Quest compared to LabCorp. Going by LC/MS, my E2 was low at LabCorp.... And slightly high at Quest. While going by immunoassay I was pretty much perfect at both labs. I'm really questioning these "accurate" LC/MS tests now.... I think I may have been chasing my tail for the past year as these tests just showed me being high, then low, then high and never really meaning anything. This really blows my mind how different results can be and makes me question why we're all using this LC/MS method instead of sticking to the immunoassay.

I doubt I'll run this experiment again - getting needles stuck in both arms on the same day isn't my idea of fun - but I wanted to post these results to see if anyone else has done something similar and to encourage you guys to run both tests at once, see what happens. I'm really skeptical now that these LC/MS tests are any good.

Cataceous

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Re: Huge Difference Between Labs
« Reply #8 on: May 15, 2019, 01:27:15 pm »
So I got another round of E2 labs done, this time including the standard immunoassay method and the LC/MS to compare. ...

Thanks for taking one for the team. It's a pretty dramatic demonstration of the fallibility of mass spectrometry-based estradiol tests. While the absolute numbers from immunoassay tests are probably somewhat high, at least the tests are consistent and repeatable.

May I ask: Were you fasting for these tests? It's not supposed to matter for estradiol, but I did notice that one of the times I had trouble with the sensitive test was without fasting. Now I always fast.
I am not a medical doctor; any suggestions are meant to be discussed with your doctor.
Age: 57, Ht: 5'10", Wt: 158 lbs
Protocol: 18 mg T enanthate subQ qod, 250 IU hCG subQ qod, 70 mcg anastrozole qod, 6.25 mg DHEA orally bid
7-12/2018 test results: TT: 800 ng/dL, E2: 31 pg/mL LC/MS-MS, DHEA-S: 264 ug/dL (49-344)—SHBG ~30 nmol/L

fifty

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Re: Huge Difference Between Labs
« Reply #9 on: May 16, 2019, 08:26:38 pm »
Blood tests = magic 8 ball operated by the wizard of oz
« Last Edit: May 16, 2019, 08:30:34 pm by fifty »

StephCurryFtw

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Re: Huge Difference Between Labs
« Reply #10 on: May 16, 2019, 11:13:14 pm »
Two out of six times I've had the LabCorp sensitive test give a result that was about half what it was supposed to be. I can't speak directly to the Quest results, but these mass spectrometry-based tests are still pretty tricky and can be very wrong when not done perfectly. A solution for some is to calibrate with the standard immunoassay test. It is idiot-proof and has been very consistent for me. The problem with these "standard" tests is some cross-reactivity to other molecules, such as C-reactive protein. But if you have low levels of the problem substances then these tests provide a good check against the sensitive tests. I mainly rely on the standard tests now, with only occasional verification via a sensitive test.

C-Reactive Protein is pretty annoying.  It messed up my labs as well with sensitive tests in the past.  How does one minimize their C-Reactive Protein prior to those tests, or is that even healthy/safe to do so?  I'll have to read up on it. 

Cataceous

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Re: Huge Difference Between Labs
« Reply #11 on: May 17, 2019, 05:28:35 am »
...
C-Reactive Protein is pretty annoying.  It messed up my labs as well with sensitive tests in the past.  How does one minimize their C-Reactive Protein prior to those tests, or is that even healthy/safe to do so?  I'll have to read up on it.

I believe C-reactive protein is a marker for systemic inflammation, and as such you'd like to minimize it all the time. If it's high enough to throw off the immunoassay estradiol tests then it's definitely too high.
I am not a medical doctor; any suggestions are meant to be discussed with your doctor.
Age: 57, Ht: 5'10", Wt: 158 lbs
Protocol: 18 mg T enanthate subQ qod, 250 IU hCG subQ qod, 70 mcg anastrozole qod, 6.25 mg DHEA orally bid
7-12/2018 test results: TT: 800 ng/dL, E2: 31 pg/mL LC/MS-MS, DHEA-S: 264 ug/dL (49-344)—SHBG ~30 nmol/L

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Re: Huge Difference Between Labs
« Reply #11 on: May 17, 2019, 05:28:35 am »